Second critical point in two realistic models of water

Abstract

Liquid-liquid critical point of water Despite a broad range of experimental observations that indirectly point out the possible existence of a liquid-liquid phase transition in deeply supercooled water, no unambiguous experiment has shown this yet. The challenges of performing experiments under such conditions are associated with the inevitable rapid crystallization of the metastable liquid state, and therefore computational simulations become a crucial alternative. Using two accurate classical models of water and long (more than 40 microseconds) isobaricisothermal molecular dynamics simulations, Debenedetti et al. provide strong computational evidence of the presence of a second metastable liquid-liquid critical point in the deeply supercooled region that has critical behavior consistent with the three-dimensional Ising universality class. Science this issue p. 289